JP2003273141A - Manufacturing method of semiconductor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve an yield by reducing the number of defective chips produced associated with an increase in the thickness of a resin layer. <P>SOLUTION: In a first technique, the resin layer 2 (coating film) formed by applying liquid resin on a substrate 1 is heated and pressed by a force plunger 4 under a condition that self liquidity is suppressed to unify the thickness of the resin layer 2. In a second technique, the resin of the protruded part of the coating film at the outer peripheral part of the substrate is removed by the blowing of gas while turning the substrate before the curing of the resin layer (coating film) formed by the applying of the resin to flatten the resin film. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a semiconductor device having a structure in which a resin layer is formed on a substrate.

[0002]

2. Description of the Related Art As a semiconductor device of this type, for example,
A semiconductor package in which a semiconductor chip is sealed with resin is known. As such a semiconductor package, a peripheral terminal arrangement type in which a metal lead electrode is arranged on a side surface of a resin package has been mainly used in the past, but in recent years, a so-called ball in which electrodes are arranged in a plane on a flat surface of the package is called. A package structure using an electrode arrangement structure called a grid array (BGA) is becoming popular.

In the BGA type semiconductor package, the projected area of the package is almost equal to the area of the semiconductor chip, so-called chip scale package (CSP).
Has been developed together with the BGA electrode arrangement structure. Such a technique enables high-density mounting of semiconductor chips on an electronic circuit board in a smaller area than before, and greatly contributes to reduction in size and weight of electronic devices.

In such a CSP structure, generally, a silicon wafer on which a circuit is formed is cut to form semiconductor chips, and individual semiconductor chips are individually packaged to complete the package. On the other hand, a manufacturing method called "wafer level CSP" is being adopted in recent years. In a manufacturing method called wafer level CSP, an insulating layer, a rewiring layer, a sealing resin layer and the like are formed on a silicon wafer to form solder bumps. Then, in the final step, the wafer is cut into a predetermined chip size to obtain a semiconductor chip having a package structure. That is, in this manufacturing method, circuits are formed by stacking on the entire surface of the wafer, and the wafer is diced in the final step. Therefore, the cut chips themselves are semiconductor chips with a package structure, and thus a semiconductor having a minimum projected area. It is possible to obtain chips.

A feature of the manufacturing method of the wafer level CSP is that all the members constituting the package are processed in the shape of the wafer. That is, the insulating layer, the rewiring layer, the sealing resin layer, the solder bumps, etc. are all formed by handling the wafer. Therefore, for example, the sealing resin layer for electrical insulation and protecting the chip and other constituent members can be obtained by forming the resin layer on the entire surface of the silicon wafer on which a large number of semiconductor circuits are formed. Generally, such a resin layer is formed by spin-coating, roll-coating a photosensitive or non-photosensitive liquid resin,
It is formed by applying by a method such as screen printing.

[0006]

However, for example, as shown in FIG. 8, the resin layer 100 applied and formed by such a method has a layer thickness in the region A near the periphery of the wafer 101 as compared with other regions. Tend to grow. It is considered that this phenomenon is partly because the resin layer 100 is deformed by the surface tension of the liquid resin so that the free surface energy is minimized. The degree of occurrence of such a phenomenon strongly depends on the characteristics of the resin, but depending on the type of resin, the range in which the layer thickness cannot be controlled is the peripheral portion 1 of the wafer.
It may reach 0 mm. In the case of FIG. 8, the wafer 10
The thickness of the resin layer in the chip manufactured by cutting out from the peripheral portion 101a of No. 1 is larger than the original design value, and such a chip may be a defective chip. Moreover, in this case, the number of defective chips increases as the chip size is reduced.

The present invention has been made in view of the above circumstances, and reduces the number of defective chips caused by an increase in the thickness of the resin layer, and as a result, manufactures a semiconductor device capable of improving the yield. The challenge is to provide a method.

[0008]

In order to solve the above problems, the following means are adopted in the present invention. That is,
The method of manufacturing a semiconductor device according to claim 1, wherein the method of manufacturing a semiconductor device includes a step of forming a resin layer on a substrate, wherein the step of forming the resin layer comprises applying a liquid resin on the substrate. A first step of forming a resin layer, a second step of performing a treatment for suppressing self-fluidity of the resin layer formed in the first step, and a self-fluidity in the second step And a third step of making the layer thickness of the resin layer uniform by pressing the resin layer suppressed. According to a second aspect of the present invention, in the method of manufacturing the semiconductor device according to the first aspect, in the third step, the resin layer is press-molded by a pressing die to make the layer thickness of the resin layer uniform. . According to a third aspect of the present invention, in the method of manufacturing the semiconductor device according to the second aspect, as a pressing die, a pressing portion that contacts the resin layer and presses the resin layer, and a purpose of the resin layer between the pressing portion and the substrate are And a layer thickness adjusting portion for ensuring a distance corresponding to the layer thickness of. A method for manufacturing a semiconductor device according to a fourth aspect is the method according to the first aspect, wherein in the third step,
The second step is characterized in that a portion of the resin layer whose self-fluidity is suppressed has a layer thickness dimension larger than that of the other portion is pressed. According to a fifth aspect of the present invention, in the semiconductor device manufacturing method of the fourth aspect, a roller is used to press the resin layer. In a method for manufacturing a semiconductor device according to a sixth aspect, in the invention according to any one of the first to fifth aspects, in the second step, the self-fluidity of the resin layer is improved by heating the substrate on a hot plate. In the third step, the resin layer is suppressed, and the resin layer is pressed on the hot plate.

According to a seventh aspect of the present invention, there is provided a method of manufacturing a semiconductor device, the method including the step of forming a resin layer on a substrate, wherein the step of forming the resin layer comprises applying liquid resin onto the semiconductor substrate. A coating step of coating, a flattening step of flattening a coating film ridge formed on the outer peripheral portion of the substrate while rotating the semiconductor substrate coated with the liquid resin, and the liquid phase after completion of the flattening step. And a heating step of heating the semiconductor substrate coated with the resin.
As the liquid resin adopted in the present invention, for example, a thermosetting resin is preferably adopted, and after being applied on the substrate in the applying step, it is heated and hardened in the heating step after completion of the flattening step. Examples of the liquid resin include a resin which is a thermosetting resin itself, a resin which is solidified by heat curing of a thermosetting component mixed in the resin, and a resin which is rapidly volatilized by heating the resin in a heating step. Various configurations such as one that cures can be adopted. Further, it may be either photosensitive or non-photosensitive.

The flattening step is a step of flattening the coating film ridge on the outer peripheral portion of the substrate while rotating the semiconductor substrate while the coating film of the liquid resin applied in the coating step is not cured. Specifically, mechanical means such as flattening the film thickness (layer thickness) of the resin layer by pressing a brush or a scraping board against the resin coating film formed on the substrate in the coating process to scrape off the excess resin. In addition to the flattening by means of the method described above, it is also possible to blow away the excess resin forming the coating film ridges by blowing gas, as described in claim 8 below. Blowing off by gas blowing is suitable in that a smooth upper surface can be easily obtained on the resin layer, as compared with flattening by scraping off by a mechanical means.

Further, in the method for manufacturing a semiconductor device of the present invention, it is preferable that in the flattening step, an inert gas is blown in a centrifugal direction onto the outer peripheral portion of the surface of the semiconductor substrate coated with the liquid resin. 8). When the inert gas is sprayed in the centrifugal direction of the semiconductor substrate on the outer peripheral portion of the semiconductor substrate coated with the liquid resin, the inert gas causes unnecessary swelling of the liquid resin coated on the outer peripheral portion of the semiconductor substrate surface. The part can be blown off and removed. Therefore, the thickness of the entire substrate can be made more uniform.

The inert gas preferably has a temperature higher than room temperature. When the inert gas is higher than room temperature,
Since the viscosity of the liquid resin can be reduced, the liquid resin can be further blown off and removed (claim 9).

It is preferable that the angle between the direction in which the inert gas is blown out from the tip of the blow-out pipe from which the inert gas is blown out and the semiconductor substrate is 5 to 60 ° (claim 10).
When the angle between the direction in which the inert gas is blown out and the semiconductor substrate is 5 to 60 °, unnecessary rising portions of the liquid resin on the semiconductor substrate can be efficiently blown off and removed. That is, the angle between the blow-out pipe and the semiconductor substrate is 5 °.
If it is less than the above range, it becomes difficult for the inert gas to come into contact with the liquid resin, so that it may be difficult to blow it off. on the other hand,
If the angle exceeds 60 °, the resin may be blown out in a direction other than the centrifugal direction of the semiconductor substrate, for example, in the center direction, which may rather make the thickness uneven.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. Here, after a liquid resin is applied on a substrate to form a resin layer (coating film), the resin layer is subjected to a treatment (heating) for suppressing self-fluidity, and then a resin layer is formed by a pressing die. And a method for equalizing the thickness of the resin layer by pressing (first method), and a semiconductor substrate on which the liquid resin is applied after forming the resin layer (coating film) by applying the liquid resin on the substrate While rotating, the resin of the coating film bulge portion generated on the outer peripheral portion of the substrate is blown off by gas blowing to be flattened, and after the flattening is completed, the semiconductor substrate is heated to cure the resin layer (second method). ) Is illustrated.

(First Method) FIG. 1 is a diagram showing an embodiment of the present invention and is a schematic diagram showing a part of the steps of a method for manufacturing a semiconductor device. The semiconductor device to be manufactured in the present embodiment is a semiconductor package manufactured by the wafer level CSP manufacturing method, and the semiconductor device may be hereinafter referred to as a semiconductor package. In the semiconductor package manufactured by the wafer level CSP manufacturing method, an insulating layer, a rewiring layer, a sealing resin layer, etc. are formed on the substrate 1 to form solder bumps. Then, in the final step, the wafer is cut into a predetermined chip size.

The substrate 1 shown in FIG. 1 is before dicing, and a resin layer 2 is formed on the substrate 1.
The resin layer 2 is formed in the step (first step) of applying a photosensitive or non-photosensitive liquid resin onto the substrate 1. Here, as a method for applying the liquid resin, a spin coating method, a roll coating method, a screen printing method or the like can be used. When the spin coating method is used, the substrate 1 is supported by a spin chuck (not shown), liquid resin is dropped on the central portion of the substrate 1, and the substrate 1 is rotated to rotate the substrate 1. The resin layer 2 having a predetermined thickness dimension is formed thereon. When the screen printing method is used, a screen mask (not shown) is placed on the fixed substrate 1 and resin is applied by a squeegee (not shown) to fill the resin in the openings of the screen mask. Then, by removing the screen mask after that, the resin layer 2 having a predetermined thickness dimension is formed on the substrate 1.

The substrate 1 on which the resin layer 2 is formed is
The step of placing on the hot plate 3 and heating (second step, prebaking) is performed. The degree of heating of the resin layer 2 in this step is preferably such that the resin layer 2 has no tackiness and no self-fluidity. More specifically, it is desirable that the solvent in the liquid resin forming the resin layer 2 be volatilized by about 50 to 95%.

Next, the heated substrate 1 and resin layer 2 are
A step (third step) of press molding with the pressing die 4 on the hot plate 3 is performed. As shown in FIG. 1, the pressing die 4 includes a plate-shaped pressing portion 5 for pressing the resin layer 3,
An outer edge portion 5a of the pressing portion 5 is provided with a layer thickness adjusting portion 6 arranged in a protruding state. Since the pressing portion 5 is in direct contact with the resin layer 2 after heating, it is necessary to form the pressing portion 5 using a material that has heat resistance and does not react with the resin forming the resin layer 2. Specifically, for example, tetrafluoroethylene resin, stainless steel, ceramics, quartz and the like can be preferably used. The layer pressure adjusting unit 6 is located between the pressing unit 5 and the hot plate 3 when the resin layer 2 is pressed by the pressing die 4, and is located between the pressing unit 5 and the hot plate 3. The function is to secure a distance corresponding to the target layer thickness, and thereby the layer thickness of the resin layer 2 is made constant. Therefore, the protruding dimension of the layer thickness adjusting section 6 from the pressing section 5 is predetermined based on the design value of the layer thickness of the resin layer 2 in the semiconductor package to be manufactured.

By pressing the resin layer 2 using such a pressing die 4, a semiconductor device 7 as shown in FIG. 2 in which the thickness dimension of the resin layer 2 is made uniform can be obtained. . That is, through the above steps, it is possible to form the semiconductor device 7 in which the resin layer 2 has a uniform layer thickness.

In the method of manufacturing a semiconductor device described above, the resin layer 2 is preliminarily subjected to a treatment for suppressing self-fluidity, and the resin layer 2 thus treated is pressed to form the resin layer 2. Since the layer thickness is made uniform, it is possible to reduce the number of defective chips caused by increasing the layer thickness of the resin layer 2, and as a result, it is possible to improve the yield. In this case, by pressing the resin layer 2, the layer thickness can be easily made uniform, and the purpose of the resin layer between the pressing portion 5 and the substrate 1 with respect to the pressing die 4 can be further improved. Since the layer thickness adjusting portion 6 is provided to secure the distance corresponding to the layer thickness, the resin layer 2 can be easily deformed as designed. Further, since the resin layer 2 is press-molded on the hot plate 3, the resin layer 2 press-molding step can be carried out immediately after the resin layer 2 heating step, and the work can be speeded up. You can

Next, test results ([Example 1-1] and [Example 1-] conducted to confirm the effect of the present invention.
2]) will be described. [Example 1-1] Here, in order to confirm the effect of the present invention, a substrate (wafer) having a diameter of 150 mm (6 inches) is used.
Was fixed to a spin chuck of a spin coater, and a photosensitive epoxy resin having a viscosity of 10 dPa · S was formed by spin coating. [Table 1] shows the distribution of the thickness (layer thickness) of the resin layer measured at each position where the distance from the substrate center is different immediately after the resin is spin-coated on the substrate.

[Table 1]

As shown in [Table 1], in the peripheral portion of the substrate (portion at a distance of -72 mm from the substrate center), the layer thickness of the resin layer is at the center portion of the substrate (at a distance from the substrate center of-). There is a portion 55% thicker than the 0 mm portion). Then, on the hot plate heated to 900 ° C.,
After pre-baking for 1 minute, a resin layer made of a photosensitive epoxy resin was formed at a pressure of 0.15 MPa with a pressing die (inner diameter 180 mm, made of stainless steel) having a pressing portion and a layer thickness adjusting portion as shown in FIG. Press molded. In this case,
[Table 2] shows the distribution of the thickness (layer thickness) of the resin layer measured at each position where the distance from the substrate center is different.

[Table 2]

As shown in [Table 2], the variation in the layer thickness of the resin layer after press molding is within 5%. That is, by applying the present invention, it becomes possible to realize a substantially uniform resin layer thickness, which was impossible in the conventional technique, in forming the resin layer over the entire surface of the substrate.

[Example 1-2] A substrate (wafer) having a diameter of 200 mm (8 inches) was vacuum-adsorbed and fixed on a wafer fixing plate of a screen printing machine, and a photosensitive polyimide resin having a viscosity of 7 dPa · S was screen-printed. A film was formed on the substrate. [Table 3] below shows the distribution of the thickness (layer thickness) of the resin layer measured immediately after the resin is applied onto the substrate and at different positions from the substrate center.

[Table 3]

As shown in [Table 3], in the peripheral portion of the substrate (portion where the distance from the center of the substrate is -97 mm), the layer thickness of the resin layer is at the center portion of the substrate (the distance from the center of the substrate is-). There is a portion that is 50% thicker than the (0 mm portion). Next, after prebaking this substrate for 5 minutes on a hot plate heated to 90 ° C., a pressing die (inner diameter 250 mm, inner diameter 250 mm, having a pressing portion and a layer thickness adjusting portion as shown in FIG.
(Made of stainless steel), a resin layer made of a photosensitive polyimide resin was press-molded at a pressure of 0.15 MPa. In this case, the distribution of the thickness (layer thickness) of the resin layer measured at each position where the distance from the substrate center is different is shown in [Table 4].

[Table 4]

As shown in [Table 4], the variation in the layer thickness of the resin layer after the press molding is within 6%. That is, by applying the present invention, it becomes possible to realize a substantially uniform resin layer thickness, which was impossible in the conventional technique, in forming the resin layer over the entire surface of the substrate.

Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and other configurations can be adopted as necessary. is there. For example, in the above-described embodiment, the resin layer 2 whose self-fluidity is suppressed by heating is pressed by the pressing die 4, but the present invention is not limited to this.
As shown in FIG. 3, of the resin layer 2 after heating, a portion 2a located in the peripheral portion 1a of the substrate 1 having a larger layer thickness than other portions is pressed by a roller 8 with a predetermined pressure, Thus, the swelled portion of the resin layer 3 may be pushed out to the outer peripheral portion of the substrate 1 to make the layer thickness of the resin layer 2 formed on the substrate 1 uniform. In this case, the roller 8
Is in direct contact with the heated resin layer 2,
It is necessary to form it with a material that has heat resistance and does not react with the resin forming the resin layer 2. For example, tetrafluoroethylene resin, stainless steel, ceramics, quartz or the like can be preferably used.

In the following, test results ([Examples 1-3]) conducted to confirm the effect of adopting such an embodiment in the present invention will be described. [Example 1-3] A substrate (wafer) having a diameter of 101.6 mm (4 inches) is vacuum-adsorbed and fixed on a wafer fixing plate of a screen printing machine, and a photosensitive solder resist having a viscosity of 180 dPa · S is formed on the substrate by the screen printing method. The film was formed on top. Then, the substrate is placed on a hot plate at 110 ° C for 1
Prebaked for 2 minutes. In [Table 5], after prebaking,
The distribution of the thickness (layer thickness) of the resin layer measured at each position where the distance from the substrate center is different is shown.

[Table 5]

As shown in [Table 5], in the peripheral portion of the substrate (portion where the distance from the center of the substrate is -45 mm), the layer thickness of the resin layer is at the center portion of the substrate (the distance from the center of the substrate is-). There is a portion that is 37% thicker than the 0 mm portion). Next, by using a roller (made of tetrafluoroethylene resin) as shown in FIG. 3, while pressing the resin layer on the peripheral portion of the substrate with a pressure of 0.1 MPa, the substrate was rotated at a spin rotation speed of 30 rpm to remove the resin layer. The raised portion was extruded to the outside of the substrate. [Table 6] shows the distribution of the thickness (layer thickness) of the resin layer measured at each position where the distance from the substrate center is different thereafter.

[Table 6]

As shown in [Table 6], the variation in the thickness of the resin layer after pressing by the roller is within 6%. That is, by applying the embodiment of the present invention, it becomes possible to realize a substantially uniform resin layer thickness, which was impossible in the conventional technique, in forming the resin layer over the entire surface of the substrate.

Separately from this, in the above-described embodiment and its modification, the resin layer 2 is formed on the substrate 1 by the spin coating method, the roll coating method, and the screen printing method. The present invention is not limited to this, and the present invention can be widely applied to a wafer level manufacturing process in which a resin layer is formed on the entire surface of a substrate (wafer).

In addition, in the above-described embodiment, in addition to the hot plate 3, a heating device such as an oven can be used for pre-baking the substrate 1 and the resin layer 2. Further, when the resin layer 2 is press-molded by using the pressing die 4, it is not always necessary to press the resin layer 2 on the hot plate 3, and the substrate 1 is moved to another position to remove the resin layer 2 from the hot plate 3. You may make it press-mold.

(Second Method) Next, the second method of the embodiment according to the present invention will be described. 4A to 4C are cross-sectional views showing a method of manufacturing a semiconductor according to the present embodiment, which is a process order. First, the substrate 12 shown in FIGS.
(Hereinafter, the substrate 12 may be referred to as a silicon wafer 12) before dicing, and the resin layer 11 is formed on the substrate 12. This resin layer 11 is
It is formed in the step (first step) of applying a photosensitive or non-photosensitive liquid resin onto the substrate 12. Here, as a method for applying the liquid resin, a spin coating method, a roll coating method, a screen printing method or the like can be used. When the spin coating method is used, the substrate 12 is supported by a spin chuck (not shown), the liquid resin is dropped on the central portion of the substrate 12, and the substrate 12 is rotated to rotate the substrate 12. The resin layer 11 having a predetermined thickness dimension is formed on the top. Further, when the screen printing method is used, as shown in FIG. 4A, the screen mask 14 is placed on the fixed substrate 12 and the resin is applied by the squeegee 15, so that the opening portion of the screen mask 14 is covered. The resin layer 1 having a predetermined thickness dimension is formed on the substrate 12 by filling the resin and then removing the screen mask 14 (see FIG. 4B).
1 is formed.

Next, as shown in FIG. 5A, in the flattening step, the silicon wafer 12 is rotated, and nitrogen gas, which is an inert gas, is sprayed in the centrifugal direction on the outer peripheral portion of the surface of the silicon wafer 12. Silicon wafer 1
By rotating 2 and blowing nitrogen gas in the centrifugal direction, a part of the liquid resin 11 (here, the coating film bulge portion) that rises on the outer peripheral portion of the surface of the silicon wafer 12 can be blown off and removed. As a result, the thickness of the liquid resin 11 can be made uniform. Alternatively, the liquid resin 11 on the outer peripheral portion can be thinned. Silicon wafer 12
There is no particular limitation on the number of rotations when rotating the liquid resin. However, if the number of rotations is too low, the liquid resin 11 may not be blown off. Therefore, it may not be possible to sufficiently eliminate unnecessary swelling portions of the liquid resin 11. .

When the nitrogen gas is blown, the nitrogen gas is blown out from the tip of the blow-out pipe 16 made of a thin metal pipe or the like. At that time, the angle θ between the silicon wafer 12 and the direction 17 in which the nitrogen gas is blown from the tip of the blow-off pipe 16 is 5 to 6.
It is preferably 0 °. If the angle 17 between the silicon wafer 12 and the direction 17 in which the nitrogen gas is blown from the tip of the blow pipe 16 is 5 to 60 °, the rising liquid resin 11 can be efficiently blown off and removed, resulting in a thickness increase. It is possible to efficiently make uniform. Further, the nitrogen gas may be sprayed at one location on the outer peripheral portion, but may be sprayed at a plurality of locations. The temperature of the nitrogen gas is not particularly limited, and may be the same as the storage temperature or the pipe temperature without adjusting the temperature, but at a temperature higher than room temperature as long as the chemical reaction of the used liquid resin 11 does not occur. Preferably there is. When the temperature of the nitrogen gas is higher than room temperature, the viscosity of the liquid resin 11 on the silicon wafer 12 can be lowered, and therefore the liquid resin 11 can be further blown and removed.

Then, as shown in FIG. 5B, in the heating step, the liquid resin 11 is heated and pre-baked on the hot plate 18, which is a heating device, to semi-cure the liquid resin 11 to form a resin layer 19. To do. Since the resin layer 19 thus formed has a uniform thickness, the semiconductor chips obtained from this wafer have little variation in thickness among the chips. The heating temperature in the heating step is 50
It is preferably ˜200 ° C. Heating temperature is 50-2
When the temperature is 00 ° C, the liquid resin 11 can be appropriately cured.

The liquid resin 11 is not particularly limited as long as it mainly contains the components of the photosensitive or non-photosensitive thermosetting resin before being cured.

Although the liquid resin 11 is applied by the spin coating method in the above-described embodiments, the present invention is not limited to this, and may be applied by, for example, a roll coating method or a screen printing method. For example, in the case of applying by a roll coating method, a silicon wafer is fixed on a movable moving table, and the moving table is moved relatively to the roll to transfer the liquid resin on the roll onto the silicon wafer. As a result, the liquid resin can be applied onto the silicon wafer. Further, in the above-described embodiment, nitrogen gas was used as the inert gas, but in addition to nitrogen gas, helium gas, neon gas, argon gas, krypton gas,
Xenon gas, radon gas, etc. can be used.

[0039]

(Example 2-1) A φ6 inch silicon wafer was fixed to a spin chuck of a spin coater, and was rotated at a spin rotation speed of 200 rpm to obtain 200 dPa · s.
The photosensitive polyimide of was coated on a silicon wafer. Then, while rotating the silicon wafer coated with the photosensitive polyimide at a spin rotation speed of 200 rpm, a stainless steel blow-out tube having an inner diameter of 2 mm installed so that the angle between the direction in which nitrogen gas blows out and the surface of the silicon wafer is 15 °. 40 to the raised part on the outer periphery of the silicon wafer.
C. Nitrogen gas was blown in the centrifugal direction. Then, the photosensitive polyimide was pre-baked by heating on a hot plate to form a resin layer necessary for the semiconductor device.
The thickness distribution of the photosensitive polyimide which is the obtained resin layer was measured. At that time, the thickness of an arbitrary diameter portion was measured, and the position in one direction from the center was set to be positive and the position in the other direction was set to be negative. The measurement results are shown in FIG. 6 and Table 7.

(Comparative Example 1) A φ6 inch silicon wafer was fixed to a spin chuck of a spin coater, and 200 dPa · s of photosensitive polyimide was applied onto the silicon wafer while rotating at a spin rotation speed of 200 rpm. Then, the photosensitive polyimide was pre-baked by heating on a hot plate to form a resin layer necessary for the semiconductor device. The thickness distribution of the photosensitive polyimide which is the obtained resin layer was measured. The measurement results are shown in FIG. 6 and Table 7.

[0041]

[Table 7]

In the embodiment, since nitrogen gas was blown to the outer peripheral portion of the silicon wafer in the centrifugal direction while rotating the silicon wafer, the resin layer on the outer peripheral portion did not become thick, and the variation was small and uniform. On the other hand, in the comparative example, since the nitrogen gas was not blown to the outer peripheral portion of the silicon wafer while rotating the silicon wafer, the resin layer in the outer peripheral portion was thick and the variation was large.

Example 2-2 A φ8 inch silicon wafer was vacuum-adsorbed and fixed on a wafer fixing plate of a screen printing machine, and 500 dPa · s of non-photosensitive polyimide was applied on the silicon wafer. Then, while rotating the silicon wafer coated with the non-photosensitive polyimide at a spin rotation speed of 100 rpm, stainless steel with an inner diameter of 1.5 mm installed so that the angle between the direction of the helium gas blowout and the surface of the silicon wafer is 35 °. Helium gas at 40 ° C. was blown in a centrifugal direction from the blow-out tube to the raised portion on the outer periphery of the silicon wafer. Then, the non-photosensitive polyimide was pre-baked by heating on a hot plate to form a resin layer necessary for the semiconductor device. The thickness distribution of the non-photosensitive polyimide was measured. At that time, the thickness of an arbitrary diameter portion was measured, and the position in one direction from the center was set to be positive and the position in the other direction was set to be negative. The measurement results are shown in FIG. 7 and Table 8.

Comparative Example 2 A φ8 inch silicon wafer is vacuum-adsorbed and fixed on a wafer fixing plate of a screen printing machine, 500 dPa · s of non-photosensitive polyimide is applied on the silicon wafer, and then on a hot plate. By heating, the non-photosensitive polyimide was pre-baked to form a resin layer to obtain a semiconductor device. The thickness distribution of the non-photosensitive polyimide of the obtained semiconductor device was measured. The measurement results are shown in FIG. 7 and Table 8.

[0045]

[Table 8]

In the example, since the helium gas was blown onto the outer peripheral portion of the silicon wafer while rotating the silicon wafer, the resin layer on the outer peripheral portion was not thick and had little variation and was uniform. On the other hand, in the comparative example, since the helium gas was not blown to the outer peripheral portion of the silicon wafer while rotating the silicon wafer, the resin layer in the outer peripheral portion was thick and the variation was large.

[0047]

As described above, according to the method of manufacturing a semiconductor device of the present invention, unnecessary resin resin swelling portions on the semiconductor substrate are eliminated, and a resin layer having a uniform thickness is formed on the semiconductor substrate. Can be made. Therefore, when cutting this semiconductor substrate to obtain a semiconductor chip,
It is possible to reduce the variation in thickness between chips and improve the yield (reduce the number of defective chips).

[Brief description of drawings]

FIG. 1 is a diagram schematically showing a first method of an embodiment of the present invention, which is a schematic diagram showing one step of a method for manufacturing a semiconductor device.

FIG. 2 is a vertical cross-sectional view of a semiconductor device formed by the manufacturing method of the present invention.

FIG. 3 is a schematic diagram showing one step in a method of manufacturing a semiconductor device according to another embodiment of the present invention.

FIG. 4 is a cross-sectional view showing a second method of the embodiment of the method for manufacturing the semiconductor device according to the present invention in the order of steps.

FIG. 5 is a cross-sectional view showing a second method of the embodiment of the method for manufacturing the semiconductor device according to the present invention in process order.

FIG. 6 is a graph showing measured values of resin thickness on a silicon wafer in Example 2-1 and Comparative Example 1.

7 is a graph showing measured values of resin thickness on a silicon wafer in Example 2-2 and Comparative Example 2. FIG.

FIG. 8 is a cross-sectional view showing a state in which a resin raised portion is formed on the outer peripheral portion of the silicon wafer.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Substrate, 2 ... Resin layer, 3 ... Hot plate, 4 ... Press mold, 5 ... Pressing part, 6 ... Layer thickness adjusting part, 7 ... Semiconductor device, 8
... roller, 11 ... liquid resin, 12 ... semiconductor substrate (silicon wafer), 16 ... blow-out pipe, 17 ... direction of blowing out inert gas (nitrogen gas), 19 ... resin layer, θ ... direction of blowing out inert gas and the above Angle with semiconductor substrate

Claims (10)

[Claims] 1. A method of manufacturing a semiconductor device, comprising the step of forming a resin layer (2) on a substrate, wherein the step of forming the resin layer comprises applying a liquid resin onto the substrate (1) to form a resin. A first step of forming a layer, a second step of performing a treatment for suppressing self-fluidity of the resin layer formed in the first step, and self-fluidity in the second step A third step of pressing the suppressed resin layer to make the layer thickness of the resin layer uniform, the method for manufacturing a semiconductor device. 2. The manufacturing of a semiconductor device according to claim 1, wherein in the third step, the resin layer is press-molded by a pressing die (4) to make the layer thickness of the resin layer uniform. Method. 3. The pressing die, which corresponds to a desired layer thickness of the resin layer between the pressing portion (5) that is in contact with the resin layer and presses the resin layer, and the pressing portion and the substrate. 3. The method for manufacturing a semiconductor device according to claim 2, wherein a device having a layer thickness adjusting portion (6) for ensuring a distance is used. 4. The third step is to press a portion of the resin layer, the self-fluidity of which is suppressed in the second step, having a larger layer thickness dimension than other portions. 1. The method for manufacturing a semiconductor device according to 1. 5. The method of manufacturing a semiconductor device according to claim 4, wherein a roller (8) is used to press the resin layer. 6. In the second step, the self-fluidity of the resin layer is suppressed by heating the substrate on a hot plate (3), and in the third step, on the hot plate (3). The method for manufacturing a semiconductor device according to claim 1, wherein the resin layer is pressed. 7. A method of manufacturing a semiconductor device, comprising the step of forming a resin layer on a substrate, wherein the step of forming the resin layer (19) comprises applying a liquid resin (11) onto a semiconductor substrate (12). A coating step of coating, a flattening step of flattening a coating film ridge formed on the outer peripheral portion of the substrate while rotating the semiconductor substrate coated with the liquid resin, and the liquid phase after completion of the flattening step. And a heating step of heating a semiconductor substrate coated with a resin. 8. The flattening step is characterized in that an inert gas is blown in the centrifugal direction of the semiconductor substrate to the outer peripheral portion of the surface of the semiconductor substrate coated with the liquid resin. A method of manufacturing a semiconductor device according to item 1. 9. The method of manufacturing a semiconductor device according to claim 8, wherein the inert gas has a temperature higher than room temperature. 10. The angle (θ) between the direction in which the inert gas is blown from the tip of the blowing pipe (16) from which the inert gas is blown and the semiconductor substrate is 5 to 60 °. 8. The method for manufacturing a semiconductor device according to 8 or 9.